串联型配电网三相电压不平衡补偿器的研究

Research on Series Power Quality Regulator for Distribution System Voltage Unbalance Compensator

针对配电网三相电压不平衡问题,提出一种采用串联型电能质量调节器补偿配电网三相电压不平衡控制方法。通过构造辅助瞬时功率,检测出非线性负载下三相电压不平衡配电网公共接入点(PCC)电压基波正序分量;通过接入点实际电压与检测正序电压的差值,得出串联变压器需要补偿的电压参考值;以参考电压为目标,对电压型变流器进行正弦脉冲控制,使串联变压器上产生相应的电压抵消电源中负序、零序分量及谐波电压分量。仿真和实验结果表明该方法能有效补偿配电网三相电压不平衡并消除谐波电压。

In view of the distribution system three-phase voltage unbalance problem, a new method to use series power quality regulator for distribution system voltage unbalance compensation is proposed.Using instantaneous power theory, it detectes the fundamental positive-sequence voltage component of point of common coupling （PCC） for the distribu- tion system under nonlinear load and three-phase voltage unbalance.Through detecting the difference of positive-se- quence voltage and the actual voltage, it gets the compensation voltage reference value that the series transformer is required. To the reference voltage value as the goal, by controlling the voltage type inverter for sinusoidal pulse meet series transformer produced a corresponding voltage can offset negative sequence, zero sequence components and har- monic voltage component.The simulation results show that, this method can effectively compensate the distribution system three-phase voltage unbalance and eliminate harmonic voltage.